Hi, Paul --
I would guess that the type of IMC conditions that
would charge the airframe up enough to disable
avionics would be of the heavy-duty variety. I
have experienced failure, in an aluminum A/C, but
it affected only comm xmit, and only briefly, and
it was inside of a cloud producing inter-cloud
lightning (don't ask; long story).
How much better a metal airframe w/o static wicks
dissipates it's static, verses a plastic one, I
don't know. I'd bet that even inside of a layer
raining out the bottom, there would be no real
problem. The real danger is filing in weather
where lightning strike is possible. See
www.open.gov.uk/aaib/dec99htm/bga3705.htm, where
it destroyed a glider, for an excellent treatise
on the topic.
---From all I've read, nothing can be done about it
(the only solution being metallic mesh laid up
within the fiberglass structure.
There are other considerations, too, for filing in
IMC at temps below freezing. How well the
laminar-flow wing can take any clear or rime
build-up, before the climb-rate goes to zip, and
the landing characteristics go crazy, is unknown
(anyone care to test it out!). And if you figure
a way to mount a heated pitot that won't melt
structure, the electrical sys may not have the
amps for the job.
Then there's the wisdom of having separate power
systems for the attitude and turn gyros, meaning
vacuum plus electrical, or dual electrical with
all electric gyros.
BTW, I'm going for IFR cert, but have the latter.
So, where you say you'd only need to "pop on top",
I'd agree with no-CB, warm-weather tops, and add
maybe 2-3 in haze as acceptable.
Regards,
Fred Fillinger, A063
Paul McAllister wrote:
>
> Hi all,
>
> In this months Sport Aviation, mention was made about the problem of static
> build up in composite aircraft when flying in clouds. Apparently this is
> due to the water molecules passing over the aircraft skin.
>
> Most of my IFR flying consists of "pop on top", but I have had a few times
> when I have been flying in very mild conditions in side clouds for up to an
> hour at a time.
>
> Given that I intend to certify my Europa for IFR I was wondering if I need
> to be giving some consideration to how I might discharge static build up.
> Any one have some knowledge or experience on this topic ?
>
> Thanks, Paul (363)
>
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